Birthday Candles Increase Bacterial Count on Cake

Like the rest of your body, the health of your mouth is dependent on the foods you eat. However, failing to develop the habit of brushing your teeth will also increase your risk of heart disease.1 Advanced gum disease may actually increase your risk of a fatal heart attack 10 times. Poor oral health also increases your risk of Type 2 diabetes by up to 700 percent, and to systemic inflammation that is linked to a number of different types of health conditions.

Unbalanced microflora in your mouth is also responsible for tooth decay. These bacteria then enter your bloodstream, increasing your levels of C-reactive protein that have an inflammatory effect on your whole body. Your oral health and hygiene help to prevent cavities and have an effect on your gut microbiome. You affect your oral microbiome with your oral hygiene habits, foods you eat and drinking fluoridated water or using fluoridated toothpaste.

By avoiding sugars and processed foods, you reduce the proliferation of bad bacteria. Proper brushing and flossing and regular cleanings with a mercury-free dentist will help ensure your teeth and gums stay healthy naturally. It’s also worth noting that while probiotics do not have a direct effect on your oral microbiome, addressing your gut flora can indeed make a big difference in your oral health.

However, the addition of bacteria from someone else’s mouth is not the type of probiotic supplementation that creates a healthy gut microbiome. Recent research found blowing on your food, or birthday cake, may increase the bacteria on the food by up to 1,400 percent.2

Blowing on Food Transfers Bacteria

Paul Dawson, Ph.D., food science professor at Clemson University, said his teenage daughter gave him the idea for a study that demonstrated large numbers of bacteria are transferred when you blow on food, such as when you blow out birthday candles.3 This is not his first study evaluating food safety, as he routinely conducts food analyses with his students at the university.

Dawson and his students simplified the study parameters by using a cake shaped Styrofoam piece, covered in foil and then frosted. The students and professor first ate pizza to simulate being at a birthday party and then placed candles in the fake cake and blew them out. Once all the students had a chance to blow out candles on their own fake cake, the frosting was retrieved, diluted in sterile water and spread on agar plates to encourage bacterial growth.

Not all of the bacteria from your mouth will grow on agar plates, but this classic method of measuring bacterial growth gave a baseline for comparison with previous studies.4 Dawson and his students found a lot of bacteria on the frosting from each of them. What surprised them was the variation between students and from blow to blow. On average, each time the candles were blown out the amount of bacteria increased 14 times.

However, in one case it increased the amount of bacteria 120 times.5 Why some people transfer more bacteria than others remains unclear. While this transfer of bacteria may sound gross, it’s typically harmless, and is highly unlikely to make you sick. If birthday cakes contributed significantly to spreading diseases, the practice would have become obsolete.

As noted by Dawson, “It’s not a big health concern in my perspective. In reality if you did this 100,000 times, then the chance of getting sick would probably be very minimal.” After all, a single French kiss can exchange as many as 80 million bacteria between mouths.6 That said, if you’re sick, it’s a good idea to refrain not only from French kissing but also from blowing out cake candles.

Contaminated Cake Unlikely to Spread Disease

Since the study was published, Dawson has heard from several people interested in how they may be able to protect their cakes from bacterial spray when the candles are blown out. There is even a current patent for a sanitary birthday cake cover and candle system7 to protect birthday cake consumers from extra bacteria.

However, most cakes won’t give you a cold and there are other ways you exchange bacteria with your family members you don’t find disgusting, such as drinking from someone’s cup or kissing. Moreover, it’s actually pretty difficult to catch a cold from saliva unless the individual has such a bad cough that viruses from the respiratory tract make it to the mouth.

Professor Emeritus Ron Eccles, former director of the Common Cold Centre at Cardiff University, commented on the ability to get a cold from saliva, saying, “The virus travels in the mucus from the respiratory system.

Unless you have a bad cough, and some of the respiratory mucus has made its way into your saliva, the cold virus will not be transmitted by kissing.” And, unless you are coughing or sneezing, and blowing candles at the same time, it’s highly unlikely you’ll get a cold from the bacteria that makes it to your birthday cake.

What’s in Your Mouth?

There are an estimated 300 different species of bacteria living in your mouth at any given time.8 Scientific photographer Steve Gschmeissner swabbed the inside of several mouths and took pictures of the bacteria under an electron microscope, demonstrating the incredible variety and scope of bacteria that live in the human mouth.

Bacteria may be found growing inside your cheeks, under your gums and on your teeth and tongue. Some of the bacteria are harmless and others help control the bacteria that causes tooth decay, the major contributors to which are Lactobacillus and Streptococcus mutans.9 Although part of the normal flora growing in your mouth, when it grows out of control and gains access to your teeth, it may lead to cavities.

Eating foods high in sugars creates a sticky film over your teeth, providing an ideal environment for bacteria in your mouth to adhere to teeth, grow quickly and cause damage.10 Even foods you may normally think of as healthy, such as raisins, are innately sticky and high in fructose, providing bacteria the nutrients they need to thrive.

The bacteria start the process by digesting sugars, producing lactic acid that lowers the pH of the mouth and encourages demineralization of the enamel covering your teeth. The bacteria also produce plaque that allows the bacteria to adhere to the teeth even longer.11 Bacteria then collect in the fissures in your teeth and a cavity begins to grow.

Poor oral health, including gum disease and multiple untreated cavities, are related to endocarditis, cardiovascular disease and premature birth or low birth weight babies.12,13 Chronic periodontitis may also lead to kidney disease and a loss of structural support for your teeth.14

Periodontal Disease and Cavities Are Dangerous to Your Health

Although you don’t want to eliminate the bacteria living in your mouth, as they serve a purpose, you do want to reduce your risk for periodontal disease and cavities. Periodontal disease may range from simple inflammation of your gums to a serious infection that affects your gums and bone that support your teeth.15 Plaque and bacteria on your teeth lead to inflammation of your gums, also called gingivitis. When left untreated it can result in periodontitis, the more severe form of periodontal disease.

In this case, pockets form around the tooth, allowing more bacteria to enter and your gum line often recedes. As this progresses, you may lose support for your teeth in your gums and bone. Tooth decay is the No. 1 chronic health problem in children.16 It is infectious, progressive and painful, and may be irreversible when left untreated. By third grade, over 70 percent of children in California have had dental caries, or cavities.

Severe dental disease may require emergency room treatment as cavities may lead to an abscess.17 These are pockets of pus that may develop in the tooth or gum that lead to pain, pressure, foul taste in your mouth and fever.18 Sometimes the pain stops when the infection destroys the pulp and nerve in your tooth, but it has not disappeared. Left untreated, an abscess may lead to sepsis as the infection travels through the rest of your body, and eventually to death.

Importance of a Healthy Oral Microbiome

Dr. Gerry Curatola, founder of Rejuvenation Dentistry, has over 30 years’ experience in biological dentistry. In this interview, he discusses the importance of your oral microbiome to your overall health, not the least of which is preventing cavities and periodontal disease.

Achieving good oral health is really about a balanced oral microbiome and not about killing the bacteria in your mouth. In other words, it’s about working with your body to achieve good health and not about following advertising that promises fresh breath after using antimicrobial agents and alcohol-based mouthwashes.

Your oral microbiome is related to your gut microbiome, but each is unique unto itself. As your mouth is the entry point to your gut, it has a protective element to defend your body from viruses and bacteria in your environment trying to gain access. Your oral bacteria also work with your saliva to begin the process of digestion. Curatola says:

“When we look at the oral microbiome, it’s an essential component of the salivary immune system; it aids in digestion, and it even makes vitamins. We are looking at ways to promote oral microbiome homeostasis. When we do that, we see amazing things happen, so amazing that you might not get the flu this winter … [I]mmune competence is a very important first line of defense, and that immune competence starts in the mouth.”

Interestingly, probiotics do not work in the mouth, so it’s not as simple as adding more beneficial microbes. As an initial step, you need to stop killing microbes in your mouth and encourage the balance of bacteria by reducing the nutrients that promote overgrowth. Curatola explains:

“Pathogens are now being recognized as resident microbes that are out of balance. When they’re under attack, they hunker down, they flick a switch … What we’re recognizing is that the same bacteria that keep us alive can have a pathogenic expression when disturbed. I have been kind of tooting the horn about getting out of the ‘pesticide business.’ I’m also speaking about natural pesticides.

Not just triclosan, clorhexidine and those synthetic types, but also tea tree oil, tulsi oil, oregano oil and other antimicrobial oils that, albeit they’re herbal, they have a potent disturbing effect on the oral microbiome.

In the mouth, you don’t want to have a ‘scorched earth policy’ or nuking all the bacteria and hoping the good bugs come back. What we found in our research is that good bugs basically have a harder chance of setting up a healthy-balanced microbiome when you disturb them, denature them or dehydrate them with alcohol-based products.”

Improve Your Oral Health Naturally

I used to be severely challenged with plaque — so much so I required very frequent visits to the dental hygienist just to keep up with it. Once I started adding fermented vegetables regularly to my diet, however, the plaque buildup was dramatically reduced.

In addition to an alkalizing, antioxidant-rich and anti-inflammatory diet, Curatola recommends eliminating detergent-based products such as toothpaste and antibacterial and alcohol- and fluoride-based mouthwashes. Again, it’s important to remember that your mouth is an organ that protects your body from dangerous infections and disease — provided it’s nourished enough to do its job. The following links can also help you find a mercury-free, biological dentist who can help you optimize your oral health: